Volume 15 - 2025 | doi: 10.3389/fonc.2025.1568524
This article is part of the Research TopicObesity, Diabetes, and Their Impact on CancerView all 6 articles
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a key adipokine secreted by adipose tissue (AT)
has emerged as a critical mediator linking obesity and breast cancer
both of which are major global health concerns
Elevated leptin levels are detected in the circulation and in extracellular vesicles (EVs) released by adipose tissue
These leptin-enriched EVs have been implicated in various stages of tumor progression
we investigated the effects of leptin within extracellular vesicles (EVs) secreted by obese adipose tissue on the functional properties and metabolism of MDA-MB-231 breast cancer cells
a model for triple-negative breast cancer (TNBC)
MDA-MB-231 cells were treated with EVs derived from the subcutaneous adipose tissue of eutrophic (EUT EVs) and obese (OB EVs) individuals
Our findings revealed that OB EVs induced significant phosphorylation of STAT3
a key signaling molecule in cancer progression
This effect was reversed in the presence of a leptin receptor antagonist
highlighting leptin's pivotal role in these processes
including reduced lactate levels and decreased pyruvate kinase (PK) activity
while increasing glucose-6-phosphate dehydrogenase (G6PDH) activity
suggesting metabolic reprogramming that supports tumor cell survival and proliferation
OB EVs also impacted mitochondrial dynamics
We observed an upregulation of fusion and fission markers and a redistribution of mitochondria toward the cell periphery
OB EVs increased the invasive capacity of MDA-MB-231 cells
an effect mediated by matrix metalloproteinase-9 (MMP-9)
our results highlight how obese adipose tissue modulates breast cancer cell behavior
with leptin-enriched EVs playing a central role in driving migration
This study underscores the importance of EVs in the obesity-cancer link and offers new insights for therapeutic strategies targeting leptin signaling and EV-mediated communication in breast cancer
Received: 30 Jan 2025; Accepted: 30 Apr 2025
Copyright: © 2025 Encarnação, Amorim, Franco, Botelho, dos Santos, Ramos-Andrade, Kraemer-Aguiar, Barja-Fidalgo, Moraes and Renovato-Martins. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY)
distribution or reproduction in other forums is permitted
provided the original author(s) or licensor are credited and that the original publication in this journal is cited
in accordance with accepted academic practice
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* Correspondence: Mariana Renovato-Martins
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An intersection on João Alfredo Street in Porto Alegre
that was redesigned during the second phase of a tactical urbanism project
helping to slow traffic speeds and reduce crossing times for pedestrians
These changes are especially important for improving the safety of the elderly and children
when drivers had become used to the new street design
WRI Brasil measured speeds at three intersections and compared them with measurements from 2017 made by the municipality
The average speed of vehicles approaching the intersections varied from 10-19 miles per hour
down from 25-32 miles per hour during free flow conditions at the same intersections three years ago
After the completion of the painted sidewalk extension and installation of new road signage
WRI Brasil and the municipality worked with the non-profit organization Engineers Without Borders and a neighborhood carpentry school to build urban furniture
even joined on a visit to the carpentry school
as students created lounges out of pallets donated by local construction companies
Street furniture creates a more active streetscape by establishing more space for people to relax and spend time in public space
the deployment of the street furniture marked the completion of this second stage in João Alfredo’s tactical urbanism intervention
To celebrate the occasion and promote the new space as a safe
accessible area for all members of the community
the city temporarily shut down traffic to the area for an open street event
As with the first open street event in March 2019
residents participated in various activities designed to encourage the new possibilities for the street
They painted the redesigned roundabout that had replaced a dangerous intersection
planted trees in new street vases and learned more about road safety
not only giving an official boost to the project but providing a valuable opportunity for the community to discuss other needs for the neighborhood
The students who built the street furniture spent time with the city officials and exchanged ideas
building an encouraging relationship between the city and its young people and laying the groundwork for future inclusive community development
The city also received donations of benches to be spread along the rest of João Alfredo
In spaces that used to have people only passing by
individuals and families began to spend more time
Porto Alegre is 1 of 20 cities participating in a national network to pilot complete streets projects under the Complete Streets Program
created by WRI Brasil in partnership with the country’s National Front of Mayors
Juiz de Fora and Campinas have completed similar complete streets pilots
and many other cities have projects in the works for 2020
The success of Porto Alegre’s first complete streets project hopefully means more to come in the future
community-driven interventions can make streets safer and create more vibrant
Bruno Batista is an Active Mobility Analyst at WRI Brasil
Ariadne Samios is an Active Mobility Senior Analyst at WRI Brasil
Andressa Ribeiro is an Active Mobility Analyst at WRI Brasil
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The João Alfredo Street intersection in Porto Alegre
Porto Alegre’s João Alfredo Street runs through the heart of the Cidade Baixa neighborhood and is known for its active nightlife
full of bar hoppers and club goers every evening
But during the day João Alfredo is almost empty
poor-quality infrastructure for pedestrians and cyclists
In early 2019, conflicts with locals over the raucous noise at night and unsafe conditions at all hours could no longer be ignored. To spark immediate, high-impact change, the Porto Alegre municipality chose João Alfredo as a pilot for a tactical urbanism “complete streets” intervention
refuge islands in the middle of the street
painted sidewalk extensions and a roundabout were all added to improve safety
the city tested the design with cones to ensure that cars
buses and other vehicles could continue navigating João Alfredo properly
the city completed the street painting and inserted road studs and bollards to protect pedestrian areas
(Ramps at the corners of the sidewalks to improve accessibility are planned but not yet completed.)
To present the new street design to the neighborhood and encourage new use of the area, the city organized an open street event, putting on a series of activities for children and residents. Local university students installed a colorful design exposition based on complete streets projects in other Brazilian cities
They also learned more about road safety through an educational campaign by the city
By encouraging the participation of a broad cross-section of the community
the city aimed to promote the street as a safe public space
Family and youth activities helped the next generation understand that streets like João Alfredo can be more than just channels for vehicles but places for people too
The Porto Alegre municipality conducted a survey during the open street event to evaluate residents’ perceptions on the changes made in the street
The survey also collected information regarding residents’ travel patterns
considering topics such as comfort and safety
The questionnaire will be applied again in six months to compare results and show the effect of changes
In this tactical urbanism project, Porto Alegre joins other cities around the world in experimenting with simple, low-cost interventions, often centered on pedestrianization of public space. In Brazil and elsewhere, these interventions are showing that a new model of street is possible
Priscila Pacheco is a Communications Analyst at WRI Brasil
Ariadne Samios is an Urban Development Analyst at WRI Brasil
The biologist and conservationist collaborates with local communities
who rescued a critical species from near extinction
and sees himself as a scientific supplement to traditional conservation
Photograph by André Dib/National GeographicFebruary 28, 2023•10 min readNational Geographic Explorer João Campos-Silva has long been fascinated by the arapaima
since before it sprung back from near extinction just over a decade ago
The precarious state of the world’s most massive scaled freshwater fish over the last century
and its recent population recovery due to efforts from local communities
formed the foundation of his current research work facilitating community-based management of fisheries to ensure the arapaima
“While most large-bodied animal species are declining
it’s the opposite trend [for the arapaima],” Campos-Silva attests
As a Brazilian scientist who has spent years building relationships with Amazonian communities
he sees his role as supplementing Indigenous Peoples’ and Local Communities’ conservation methods with scientific expertise
bringing traditional knowledge to academic science
For this reason he refers to himself as “a bridge” between knowledge systems
Campos-Silva’s work “does not involve local people,” he clarifies
Concerns about arapaima stocks first surfaced after local fishermen began returning home with empty nets
Commercial overfishing was depleting fish stocks
the arapaima is served for top dollar in restaurants across Brazil
Its symbolism in some Indigenous cosmology equates the arapaima’s importance with that of humans
there was interest at every level to see them back in the water
Local communities in partnership with researchers and environmental stakeholders from Brazil’s Mamirauá Sustainable Development Institute developed model in 1999 that established protected lakes where fishing and hunting were prohibited
local fishermen were allowed to harvest sustainable fish quotas that brought the arapaima back from near collapse
and rippled into economic and social benefits for families in the Solimoes River
The model demonstrated that such megafauna declines are not only reversible
but when harvested legally and sustainably
“It’s very important to be clear that the model was developed by locals,” he stresses
Campos-Silva is vehemently opposed to the idea of himself as a central figure
but wholly owns his role as a scientific partner
to further understanding of the intricate role the Amazon River Basin plays in maintaining the entire ecosystem of the Amazon from the Andes to the Atlantic
who have both entered their 13th year of scientific research and conservation in the Amazon
returned from their latest trip to the field in late 2022
for which they partnered with local and indigenous communities to assess the health of six key aquatic species
Crittercams and GPS tags—including the first to ever be fitted on an arapaima—will track the movements of giant Amazonian river turtles
The data will map the perimeters of new conservation zones in an effort to scale up protection of healthy wildlife and human lives
A giant South American river turtle (Podocnemis expansa) headed towards the Juruá River after spawning
at the Medio Juruá Extractive Reserve. Photograph by André Dib/National GeographicFifty Juruá River communities are collaborating with Campos-Silva and Scabin to complete the work
“People realize that through conservation they can have a better life,” Campos-Silva says
“People are proud to be a positive example in the Amazonia
Our research shows that the arapaima management has boosted their self-esteem,” and impacted more than just fishermen
Women are forging their independence in new ways by filling jobs on boats
and the growing income streams are helping eradicate general poverty
the day-to-day work doesn’t come without challenges
Trying to track down aquatic wildlife can be unpredictable
as is the nature of working in remote areas
and sometimes the demand for scientific results outpaces the reality of what the team’s collection bandwidth looks like on the ground
To truly work in tandem with local communities means understanding their needs
and to truly understand people is to not hurry
“We need to be there to stay for a long time without the data collection
to talk about football or to play music together.” Justifying time for relationship-building is unorthodox for research proposals
Biologists monitoring the giant South American river turtle (Podocnemis expansa) population
Elerson Barbosa (L) and João Alfredo da Mata (R)
examine one of the turtles at the Medio Juruá Extractive Reserve. Photograph by André Dib/National GeographicInvesting time is how Campos-Silva came to understand the plight of the arapaima and how he could be a part of saving it
He spent two years living with local communities as part of his doctoral research in ecology
witnessing the pivotal role of human societies in preserving wildlife
“Local people were always linked to threats
It’s a one-sided misconception he aims to address
should serve as a blueprint for the protection of habitats
He’s hopeful the conservation methods used to revive arapaima populations will work on the five other species he’s actively working to protect
The success story is also a signal of optimism for a simultaneously prosperous ecological and economic future for the Amazon
“I think optimism is a survival strategy,” he says
“The ability to imagine another future can create hope
and the power to fight for a better life and a better world.”
ABOUT THE WRITERFor the National Geographic Society: Natalie Hutchison is a Digital Content Producer for the Society. She believes authentic storytelling wields power to connect people over the shared human experience. In her free time she turns to her paintbrush to create visual snapshots she hopes will inspire hope and empathy.
While many may have heard the word "morna" for the first time in early November when UNESCO declared the music Intangible Cultural Heritage
84-year-old Armando DePina can trace his memories of it to his childhood on the Cabo Verdean island of Brava
"My mom liked to sing it around me when I was a child," DePina recalled in Portuguese
"She thought that I would like to sing them
By the 2000s, DePina's humble Seekonk home would become a site of pilgrimage for Cabo Verdean musical royalty — such as Cesária Évora, Mayra Andrade, and Tito Paris — visiting to pay homage to the man who entered into the hearts of his countrymen with one song
"I was still a young boy when I immigrated to America," he said, recalling his inspiration for the song "Mar é morada de sodade [The Sea is Nostalgia's Home]
and that kept me really close to my mother
"My friend brought me to Nantasket Beach [in Hull
and it was a beautiful sunset," he continued
"I just felt such a longing for my country at that moment..
So I just sat down and began to write that song about Nantasket."
DePina changed his posture in the wooden seat of his home's kitchen table and prepared a show for an audience of three — a Journal reporter and photographer
"One evening in the sunset I was walking along Nantasket Beach," he crooned in kriolu — a Portuguese-based creole used for everyday speech in the archipelago
"It reminded me of the beach at Furna and overwhelmed me with so much nostalgia that I cried."
DePina's soft-spoken speaking tone was replaced by a booming tenor
to perform a song of his that many Cabo Verdean immigrants view as their anthem
"The sea is nostalgia's home," DePina sang
his voice rising and falling as they traced the contours of emotion the lyrics created
"It separates us from our mothers and friends..
João Rosa, the director and founder of the Pedro Pires Institute for Cape Verdean Studies at Bridgewater State University
said that though its beginnings are unclear
morna's foundations are a reflection of cultural mixture that happened on the islands throughout their history
"There are multiple sources you can consult and multiple sources will tell you different things about its roots," Rosa said. "Some people say for example that fado [a traditional style of Portuguese music] is one underlying source of morna
but Cabo Verde had always been exposed to rhythms from multiple countries
"To pinpoint the historical roots of morna
one would have to say it's a kind of amalgamation of different rhythms
But there are characteristics that are uniquely Cabo Verdean."
Rosa added that each island — including Brava
Boa Vista and other islands — has its own themes and language that it applies to the music
to create what is truly a style native to the macaronesian islands
"The morna itself is a marker of humanity," he said
"It would be difficult for you to think of flamenco and not think of southern Spain
João “Fefe" Alfredo remembers his mother singing morna tunes as she went about cleaning their home on Brava
She went on to enroll him in a local parochial school that specialized in music
Yet she was not so much of a fan of his first forays into the genre
"I was about 16 years old when I would sneak out of the house to participate in the serenades," Fefe
"I remember that my first serenade was for my friend Jorge Vicente
who was in love with a girl in another town
"I remember the skies that night were clear and being there
Yet the music for him is about more than just the romance that got him to perform
"I think that morna came from people's deepest feelings," he said
"They wanted to be able to show the full spectrum of emotions
and their passion for their partners and family."
DePina said that he began to perform publicly in a similar fashion
when men in their 20s who liked his voice asked him to accompany them on their serenatas
"I had to ask my mother's permission to go out with those boys at night
because she thought I was still too young for that," DePina said
"She would have never let me go out with them if she thought I was looking for women."
Yet DePina said that it was his experiences as an immigrant that truly deepened his understanding and feelings for the music that had always been a part of him
It is presence and absence and sea and sky
"It is a salute to our homeland," he continued
it is a prayer for our islands of Cabo Verde."
That connection between the islands and their diaspora populations is a critical aspect of what makes the music so unique
"It's kind of a dialectical process because on the one hand you have the people of Cabo Verde who express this kind of longing for people who have left through morna," Rosa said
"On the other hand you have people here that compose incredible pieces of music here that look backward towards the land and people they left behind
"Armando DePina's 'Mar é morada de sodade' is an incredible piece," he continued. "If you look at other composers like Morgadinho's 'Cabo Verde One 2000,' the conversation is two ways
It is both the longing of people who left that look back and the sorrow of what they left behind and those who remained that have a forward-looking view," thinking of the opportunities beyond the sea
Alfredo said that he brought the music with him when he immigrated in the 1970s
I formed a group with some friends called Midnight Star," he said
"Our first show was at a club that used to be on Fall River Avenue in Seekonk
but by far my favorite style to perform is Morna."
The announcement by UNESCO brought happiness to Alfredo's heart
though he reacted calmly at first from Cabo Verde
and there was this fantastic reaction where people truly celebrated
"We were always waiting and hoping for the music to be recognized by the world," he added
"Because morna is a music that beats in the heart of every person."
"This moment is incredibly significant because it marks the contribution of Cabo Verdeans throughout the world," Rosa said
While DePina finds the recognition significant
he expressed concern that the music would die along with older generations
but the way things are with younger generations today
"They like to listen to other styles like coladera or rap now."
young people are listening to that music now," he said
they will want to connect with their roots and start to listen to morna again
On Twitter: @Kevprojo
Metrics details
Metastatic disease remains the leading cause of death in cancer and understanding the mechanisms involved in tumor progression continues to be challenging
This work investigates the role of manganese in tumor progression in an in vivo model of tumor growth
Our data revealed that manganese accumulates within primary tumors and secondary organs as manganese-rich niches
Consequences of such phenomenon were investigated
and we verified that short-term changes in manganese alter cell surface molecules syndecan-1 and β1-integrin
enhance collective cell migration and invasive behavior
Long-term increased levels of manganese do not affect cell growth and viability but enhance cell migration
We also observed that manganese is secreted from tumor cells in extracellular vesicles
we describe exogenous glycosaminoglycans that counteract manganese effects on tumor cell behavior
our analyses describe manganese as a central element in tumor progression by accumulating in Mn-rich niches in vivo
affecting migration and extracellular vesicle secretion in vitro
Manganese accumulation in specific regions of the organism may not be a common ground for all cancers
it represents a new aspect of tumor progression that deserves special attention
The role of metals in cancer progression remains to be further investigated
confirming that this structure is accumulating Mn in a time-dependent manner
Manganese distribution is affected during tumor progression
Control and tumor-bearing mice were analyzed regarding elemental tissue content and distribution by X-ray fluorescence
Elemental distribution maps from (a) primary tumors—examples from two tumor-bearing mice; (c) lungs—from one control and one tumor-bearing mice; and (e) livers—from one control and one tumor-bearing mice were built from the acquired spectra; map color code: green (Mn—manganese)
Maps’ dimensions for primary tumor: 7.6 mm × 6.0 mm (left panel) and 6.9 mm × 7.7 mm (right panel); lungs: 8.6 mm × 6.2 mm (control) and 3.2 mm × 4.5 mm (tumor-bearing); livers: 11.0 mm × 14.0 mm (control) and 9.3 mm × 13.7 mm (tumor-bearing)
White arrows indicate regions where manganese was found to be in highest concentration (high-Mn niches)
Elemental concentration of manganese from these regions were plotted for all (b) primary tumors
Primary tumors were analyzed from week 1 to week 5
lungs and livers were analyzed at week 5 of tumor progression; peripheral blood was analyzed from week 0 to week 5 of tumor progression and bone marrows were analyzed at weeks 3 and 5 of tumor progression
Control mice samples are represented in black symbols
tumor-bearing mice samples are represented in red symbols
Units are expressed in concentration as ppm (parts per million)
Kruskal–Wallis test and Dunn’s multiple comparison post-test
(tumor-bearing) N = 10; Livers (control) N = 11
(tumor-bearing) N = 17; Peripheral blood (week 0) N = 3
(week 5/tumor-bearing) N = 5; Bone marrow (week 3/control) N = 9
Observed alterations indicate that the presence of a primary tumor induced by the inoculation of LLC cells into C57BL/6 mice systemically affects Mn distribution within the organism in a time-dependent manner
Mn-rich niches are found within primary tumor-specific regions
To understand which possible tumor-related mechanisms were affected by Mn
we decided to analyze LLC cell behavior in vitro
Analyses were performed as close as possible to in vivo conditions
culturing and testing LLC cells in full medium conditions and observing the effect of Mn-enriched medium on cell growth and behavior
First, LLC cells were exposed to increasing MnCl2 concentrations and cell growth was evaluated after 24 h of incubation (Fig. 2). We observed that LLC cell growth was not affected by added concentrations of MnCl2 up to 10 µM. Therefore, we supplemented 5 µM of MnCl2 to complete cell medium in the following experiments.
LLC cell survival was evaluated after 24 h of incubation with different MnCl2 concentrations
Cell number represents adhered live cells only
*p < 0.05; **p < 0.01; ***p<0.001
two-way ANOVA and Bonferroni’s multiple comparison post-test
Manganese promotes tumor cell migration in vitro and heparin counteracts its effects at a non-anticoagulant concentration
LLC cells migration was evaluated in matrigel-covered transwell chambers
Transmigration was analyzed after 3 h of incubation in control and Mn-treated (MnCl2 5 µM) conditions
Transwell inserts were (a) stained and imaged for (b) cell quantification
UFH (bovine unfractionated heparin—0.1 ng/mL)
one-way ANOVA and Bonferroni’s multiple comparison post-test
We were able to observe that UFH was capable of blocking MnCl2 effect on cell invasion
Manganese modulates tumor cell migration pattern
LLC cells migration pattern was evaluated in wound healing assays by intermittent (a
Cells were (a) imaged and (b) total migrated distance was quantified
(c) Time lapse images—example from a Mn-pretreated cells migration video—were also acquired and compilated into videos for (d) collective migration quantification
(e) Single-cell speed was calculated from videos
UFH (bovine unfractionated heparin—0.1 ng/mL); pre-Mn (MnCl2 5 µM 1 h pretreatment prior to migration)
one-way ANOVA test and Bonferroni’s multiple comparison post-test
Other tumor cell lines were evaluated regarding their migration potential in wound healing assays after brief exposure to MnCl2-supplemented medium (SI Appendix, S2a–c)
Data revealed that HeLa cells present similar behavior compared to LLC cells
B16 and MDA-MB-231 cell lines do not respond significantly to Mn
an indication that underlining mechanisms regulate cell migration
We have also tested tumor cell behavior in the presence of other divalent metals known to affect integrin function, magnesium (Mg) and zinc (Zn). We could observe that MgCl2 does not affect tumor cell survival or migration (SI Appendix, S3a, b), while ZnCl2 is cytotoxic at 500 µM, but does not affect cell migration (SI Appendix, S3c
Tumor cells cultured in manganese-low and manganese-high conditions present different migration patterns
LLC cells were cultured in Mn-low and Mn-high conditions for 48 h and (a) cell growth was evaluated by counting live
(b) Cell viability was evaluated by the MTT assay
LLC cell migration pattern was evaluated in wound healing assays by intermittent monitoring at 0 h and 12 h
Cells were (c) imaged and migrated distance was (d) quantified
Mn-low (standard high glucose DMEM + Mn-low FBS); Mn-high (standard high glucose DMEM + Mn-high FBS)
Cell growth assay N = 4; MTT assay N = 6; wound healing assay N = 6
Tumor cell-derived extracellular vesicles are enriched in manganese and affect tumor cell migration
LLC cells-derived extracellular vesicles were concentrated by ultracentrifugation
(a) EVs quantification and size determination
(b) CD63 and syntenin-1 detection by Western blotting
EV-free conditioned medium and basal medium were analyzed by X-Ray Fluorescence
Control cells—white bars; Mn-pretreated cells (Mn) – black bars
(d) Wound healing assays of LLC cells incubated with extracellular vesicle-enriched medium from control and Mn-pretreated LLC cells
one-way ANOVA and Bonferroni's Multiple Comparison Test
Cu and Zn) did not present differences in concentration between control EVs and pre-Mn EVs
We have followed the wound healing assay protocol and collected cells at 8 h of migration
Syndecan-1 expression did not present significant changes between conditions when analyzing total cell population
Manganese affects β1-integrin and syndecan-1 expression in tumor cells
Confocal microscopy images of (a) immunostainings for β1-integrin
ZY axis projections were generated from higher magnification images of β1-integrin and syndecan-1 merged stainings
Scale bars are 25 µm (lower magnification) and 10 µm (higher magnification)
Images were quantified regarding fluorescence intensity for (b) β1-integrin
(c) syndecan-1 and (d) phalloidin-Alexa 488
(e) β1-integrin and syndecan-1 colocalization rates
which could explain the differences in molecules’ expression found between total cell population and cells in the migration edge
These data indicate a possible relationship between high-Mn niches and syndecan-1 in our in vivo mouse model of tumor growth
Ascidian dermatan sulfate counteracts migration-promoting effects of manganese on tumor cells
LLC cell migration was evaluated by wound healing assays after brief exposure to manganese followed by treatment with an ascidian dermatan sulfate (DS)
Cells were (a) imaged at 0 h and 12 h and migrated distance was (b) quantified
Sample contamination by free Mn was evaluated by analyzing water collected from the last dialysis day
We could observe that background levels are low and not responsible for the significant amounts detected in the glycans dialyzed solutions
affect Mn content and distribution in vivo
we treated tumor-bearing mice with UFH at 2 and 4 weeks of tumor development with local subcutaneous injections of UFH at a non-anticoagulant concentration
primary tumors were collected for XRF analyses and Mn quantification and mapping
We were able to verify that both experimental groups
tumor-bearing mice (control) and UFH-treated tumor-bearing mice
presented unchanged average Mn and Mn-rich regions (SI Appendix
Mn is particularly relevant in cell migration and survival
two central aspects of tumor progression and metastasis
In this work we have focused our investigations on Mn distribution and accumulation in primary tumors and its effects on tumor cell behavior
We aimed to observe trace elements’ changes imposed by tumor progression and their contribution to microenvironment modulation
In depth XRF analyses of tumor-bearing mice revealed that LLC-induced ectopic primary tumors accumulate Mn in a time-dependent manner
Accumulation occurs not only when average Mn was measured in the tissue
but much more intensely in specific regions of approximately one to four pixels (360–1440 µm2) in XRF imaging
we did not detect average Mn changes in livers and lungs
an indication that Mn distribution is affected by tumor progression
Due to the fact that tumor-bearing mice bone marrows presented elevated average Mn levels
while peripheral blood presented a decrease at the same stage of tumor progression
we conclude that occurrence of Mn-rich niches in primary tumors and lungs
as well as elevated Mn levels in bone marrow are regulated processes strongly associated with tumor progression
the fact that different tissues presented varied profiles of Mn distribution indicates that tissue Mn levels are not simply a result of Mn availability
they may be the result of multiple regulation mechanisms
Mn-binding molecules alone or associated with Mn-related ions
Our data revealed an interesting aspect of Mn imbalance during disease progression: occurrence of Mn-rich niches in the absence of obvious Mn systemic changes
detailed analysis of the niches revealed that primary tumors present Mn alterations before distant organs
Mn-rich niches from primary tumors present correlated alterations in P
while Mn-rich niches from lungs and livers only present alterations in Mn
These data indicate that Mn alterations initiate in primary tumors and may influence the occurrence of Mn-rich niches in healthy tissues
therefore the detected elevated levels of Mn within tumor-bearing mice bone marrow may be due to the arrival of extracellular vesicles expressing Mn-activated integrins released by cancer cells from primary tumor
We hypothesize that LLC cells continuously retain Mn from circulation
resulting in average elevated Mn levels in primary tumors
as well as formation of Mn-rich niches through extracellular vesicle delivery
Multi-elemental analyses of Mn-pretreated cells-derived EVs revealed that Mn is the only detected element at significantly different levels compared to control EVs
This information points toward EVs as one of the likely routes of Mn distribution from the primary tumor to distant organs during tumor progression
we have analyzed different tumor cell lines and found that Mn accumulation does not occur in all cells
for instance HeLa and B16 cell lines retain Mn after brief in vitro exposure
These additional data confirm the specificity of Mn retention
internalization and secretion in some types of tumors
tumor-bearing animals present a unique feature
We show that these niches are formed in a time-dependent manner after Mn accumulation in the primary tumor and reach impressive levels in advanced stages of tumor progression
Further investigations of alterations in Mn transport mechanisms in tumor cells are an interesting and relevant perspective for the field
Mn could be solely responsible for affecting syndecan-1 cell surface distribution pattern if proteoglycan internalization or shedding were promoted by binding to the cation
these processes could also be mediated by proteoglycan-mediated Mn presentation to its receptor on the cell surface
High magnification confocal analyses of syndecan-1 and β1-integrin immunostainings revealed that these molecules can be found on the cell surface
confirming that both processes are equally possible
syndecan-1 immunostainings of primary tumors and livers from control and tumor-bearing mice indicate that this proteoglycan may be involved in Mn distribution in vitro
Mn-rich niches in distant organs are discrete in comparison to primary tumors, nevertheless they can also be found clustered near vessels (Fig. 1e)
Following the time-associated evolution of this pattern
we hypothesize that distant organs may receive Mn from primary tumors
forming Mn-rich niches later in tumor progression
Mn distribution from primary tumors can occur by secreting soluble factors or vesicles into the circulation
We have also detected that the remaining vesicle-free medium contains the same levels of Mn concentration as basal medium
confirming that EVs are the preferential route for Mn secretion in these cells
The release of Mn-rich EVs in the circulation would explain the observed pattern of Mn-rich niches without impacting Mn average tissue levels
Taking into consideration Mn-dependent processes of cell migration and survival
we hypothesize that occurrence of Mn-rich niches in distant organs may be a characteristic of microenvironment modulation
Findings show that MnCl2 5 µM mainly stimulates transmigration through type I collagen (chemotaxis assay)
while transmigration through matrigel (chemoinvasion assay) is more pronounced at MnCl2 100 µM
Our group has found that MDA-MB-231 cells do not retain Mn and do not present enhanced migration in the wound healing assay at MnCl2 5 µM
in consonance with the results described above by Luparello (2019)
differences in cell behavior according to Mn concentration and ECM setup may arise from variations in Mn transport mechanisms and in the expression profile of ECM-binding cell surface molecules
LLC cells were also cultured in Mn-modified media (Mn-low and Mn-high) and we could see that cell viability was not affected by these culture conditions
we verified that basal migration is not affected in Mn-low culture conditions
when cells are pretreated with a pulse of high Mn
Mn-low cells migrate slightly less than control cells
LLC cells cultured in Mn-high conditions migrate similarly to pre-Mn cells (control cells + Mn pretreatment)
pre-Mn treatment in Mn-high cells does not further enhance migration
These data reveal that tumor cell migration is affected by both short-term and long-term Mn exposure
This model of in vitro tumor cell migration indicates that tumor cells in vivo may experience similar conditions and present enhanced migration when near or within Mn-rich niches
Other tumor cell lines were analyzed regarding migration behavior after brief exposure to Mn-rich culture medium
cell lines able to retain Mn may (HeLa cells) or may not (B16 cells) respond to Mn
among the tested cell lines the one that does not retain Mn
also does not change its migration pattern upon Mn stimulation (MDA-MB-231 cells)
our analyses point to a time-dependent process that promotes the formation of Mn-rich niches
These niches are prominent within primary tumors; however
they can also be observed in distant organs
Our results show changes in LLC cells migration even after a short-term exposure to Mn from invasive to highly invasive
β1-integrin and syndecan-1 are found colocalized after manganese short-term exposure in migrating cells
EVs also change from presenting low manganese content to higher manganese content
the overall results revealed an unexplored role of Mn in tumor progression and possible mechanisms involving its effect on tumor cell motility
Mn accumulation in specific regions of the organism may not be a common ground for all cancers
nevertheless it represents a new aspect of tumor progression that deserves special attention
Cells were cultured under standard conditions at 37 °C and CO2 5% atmosphere
Cell culture medium was composed of DMEM (Sigma-Aldrich) supplemented with fetal bovine serum (FBS) 10% (v/v) (Vitrocell) and glucose 4500 mg/L (Sigma-Aldrich)
Cells were passaged with a trypsin-EDTA solution (trypsin 0.25% and EDTA 1 mM)
Protease-free cell detachment was achieved by incubating cells in a Ca2+ and Mg2+-free PBS solution with EDTA 1 mM
followed by detachment with a cell scraper and further pipetting
Cell viability was assessed by counting detached cells using a Neubauer chamber in trypan blue 0.2% solution
Each quantification was performed at least three times
Cell lines used in this work were LLC (mouse Lewis lung carcinoma
LCC cells were seeded in 24-well plates (6 × 104 cells/well) and after cultures reached 80% confluence
cells were incubated for 24 h in increasing concentrations of MnCl2 (5
Cells were harvested by enzymatic treatment and viable cells were quantified in a Neubauer chamber using trypan blue
Semi-confluent LLC cells were detached using the protease-free method and quantified as described above
transwell inserts 8 µm pore-size (Corning) were placed on 24-well culture plates and the top chamber was incubated with 100 µL matrigel (BD Biosciences) diluted in FBS-free medium to 1 mg/mL
Inserts were incubated at room temperature for 2 h
excess medium was removed by gentle aspiration and inserts were prepared for transmigration
Bottom chamber was filled with 650 µL culture medium supplemented with FBS 10%
while top chamber received 100 µL FBS-free medium with a total of 105 cells
Plates were incubated in standard culture conditions for 3 h
when inserts were collected for processing
Quantification of transmigrated cells was achieved by removing inserts from culture plates
followed by gentle scraping of non-transmigrated cells from the top chamber using a cotton swab
fixed and stained in a crystal violet 0.5% (m/v) solution in methanol 20%
and cell quantification was performed using ImageJ software 1.52a
Cells were cultured in 6-well plates until 80% confluence
then culture medium was changed to control (regular culture medium) or pre-Mn (regular culture medium with the addition of manganese chloride (MnCl2—Sigma-Aldrich) 5 µM
Cells were incubated in these conditions for 1 h
cells were rinsed and mechanically removed from the plate in a cross-shaped pattern using a sterile P1000 tip
Cells were rinsed again for removal of cell debris and incubated in control (regular culture medium) or polysaccharide-treated (regular culture medium with the addition of unfractionated bovine heparin—UFH or ascidian-derived dermatan sulfate—ascDS at 0.1 ng/mL) for 12 h
In order to evaluate cell migration and wound closure
using the cross center as a reference at 0 h and 12 h
Migration was quantified using ImageJ software and expressed as the percentage of migrated distance relative to the original wound width
An automatic microphotography system was used to monitor migrating cells under standard culture conditions and generate time lapse videos
Images were compiled into videos that were analyzed regarding migrating pattern (collective cell migration) and single-cell speed (ImageJ software)
Pellets were discarded after each centrifugation round
the remaining supernatant was ultracentrifuged (Beckman 70Ti rotor) at 100,000g for 70 min
The extracellular vesicle-enriched pellet was washed in PBS to eliminate contaminating proteins and centrifuged one last time at 100,000g for 70 min
The final pellet was resuspended in 100 µl of PBS
A Nanoparticle Tracking Analysis – NTA Zetaview - was used to monitor separation
exosomes previously purified were lysed in 50 mM HEPES
1 µg/mL leupeptin and 1 µg/mL soybean trypsin inhibitor
Total protein content in the exosomes extracts was determined by BCA method
Lysates were denatured in sample buffer (50 mM Tris·HCl
and 0.001% bromophenol blue) and heated in boiling water for 3 min
Samples (10 µg total protein) were resolved by 15% SDS-PAGE and proteins transferred to polyvinylidine difluoride membranes
Molecular weight standards were run in parallel
Membranes were blocked with Tween-TBS (TBS
0.01% Tween 20; T-TBS) containing 5% BSA and probed with primary antibody (1:500) overnight at 4 °C
Primary antibodies used in western analysis were anti-CD63 cat: 10628D and anti-Syntenin-1 cat: PA528813 (Invitrogen
The membranes were rinsed with T-TBS and incubated for 1h at room temperature with HRP-conjugated secondary antibody (1:5000)
Immunoreactive proteins were visualized by the ECL detection (GE
LLC cells were submitted to wound healing assays incubated with extracellular vesicles (EVs) enriched medium containing 4 times more EVs than a naturally conditioned medium
Cells received EVs from naïve LLC cells (control EVs) and from MnCl2 pre-exposed cells (pre-Mn EVs)
C57BL/6 male and female mice between 8 and 12 weeks of age were anesthetized and inoculated subcutaneously in the posterior dorsolateral region with 5 × 105 LLC cells in 60 µL serum-free DMEM as vehicle (tumor-bearing group)
whereas control animals were inoculated with vehicle only
Animals were randomly assigned to experimental groups
comprising a minimum of five specimens per experimental group in order to accurately assess variations between specimens
All experimental groups were kept under standard conditions and daily monitored for vital signs
behavior and tumor size from 0 to 5 weeks of tumor development
Animals that presented signs of possible discomfort were anesthetized with a combination of xylazine and ketamine and submitted to a cervical dislocation procedure according to the Brazilian animal experimentation guidelines
Death was confirmed by observing all of the following: absence of breathing movements
These animals were excluded from the experiments
Tissue samples were collected in order to investigate tumor progression in a time-dependent manner
in addition to peripheral blood and bone marrow were harvested at weeks 0–5 and processed for analyses
briefly and superficially fixed in 4% paraformaldehyde for 5 min and cryopreserved in OCT (Optimal Cutting Temperature compound – Tissue-Tek) for further sectioning
Liquid tissues were collected fresh and immediately processed for further analyses
All procedures involving animal experimentation were approved by the Federal University of Rio de Janeiro Animal Experimentation Committee (protocol number: 015/18) and were performed in accordance with the Brazilian guidelines for scientific use of animals
This work is in compliance with the ‘Animal Research: Reporting of In Vivo Experiments’ (ARRIVE) essential 10 guidelines
LLC cells were cultured on RS glass slides (Nunc) covered in growth factor-reduced matrigel (BD Biosciences)
cells were submitted to the migration wound healing assay for 8 h
Cells were fixed in 4% paraformaldehyde for 10 min
cells were rinsed with PBS and incubated in blocking solution (2% bovine serum albumin in PBS) for 30 min
followed by incubation with Triton 0.1% for 5 min
Primary and secondary antibodies were incubated separately for 90 min each in the following order: rat anti-syndecan-1
slides were mounted in anti-fade mounting medium Vectashield (Vector Laboratories) with DAPI
Antibodies used for immunostaining were diluted in 0.5% albumin in PBS and are anti-CD138 (1:100 - RD Systems) and anti-β1 integrin (1:100 - Santa Cruz Biotechnology)
Images were acquired on the confocal microscope system TCS SPE (Leica) and processed using LAS X software (Leica)
Cells were imaged using a 10X objective lens and a 40X oil immersion objective lens (with additional 3X zoom)
Images were acquired in stacks of 500 nm thickness and the number of stacks varied according to sample height
Traditional widefield immunofluorescence images were acquired using an Axio Imager A1 microscope and Axiovision System software (both Zeiss; Oberkochen
Mn-low and Mn-high FBSs were filtered using a 0.22 µm syringe filter (Millipore) in order to ensure all solutions were sterile
Mn-low and Mn-high manipulated FBS were both prepared from the same initial solution in order keep the same overall composition for both conditions
ICP-OES analyses were performed in order to define elemental composition of modified fetal bovine sera (SI appendix)
LLC cells were cultured in standard conditions until experiments were performed
LLC cell survival was evaluated by seeding 2.6*104 cells/cm2 into 6-well plates in standard cell medium
medium was carefully exchanged to experimental media as: control medium
Cells were cultured for 48 h and quantified in a Neubauer chamber using trypan blue
Cell viability was evaluated using the MTT assay
LLC cells were cultured in standard and respective experimental conditions for 48 h in 96-well plates
Cell viability was assessed by incubation with tetrazolium salt (MTT
and formazan crystals were dissolved in 200 µL dimethyl sulfoxide (DMSO
Absorbance at 560 nm was acquired using SpectraMax Plus microplate reader (Molecular Devices) and analyzed using Softmax Pro software (Molecular Devices)
LLC cell migration in Mn-low and Mn-high conditions was evaluated following the same protocol described for cell migration wound healing assay
Cells were seeded onto 6-well plates in standard culture conditions and
After 12 h of incubation in the modified media
cells were briefly exposed to a Mn pulse by incubation in their respective medium with added MnCl2 5 µM
cells were rinsed and the scratch was done
Cells were imaged at 0 h and 12 h of migration in their respective modified medium and were named: control
Mn-low + pre-Mn (Mn pulse before migration)
Collection of ascidian specimens was authorized by the Brazilian regulatory agency ICMBio
under the protocol number 66457-1 (SISBIO)
Unfractionated bovine heparin (UFH) and ascidian dermatan sulfate (ascDS) were tested for manganese binding
A total mass of 1 mg of each polysaccharide was incubated in MnCl2 1 M for 24 h at room temperature
X-ray fluorescence was used to assess polysaccharide-bound manganese
Water from the last dialysis day (control water) was used as a control for residual free manganese
Statistical analyses were performed using GraphPad Prism 5 for Windows
Kruskal–Wallis test with Dunn’s post test was applied to all in vivo experiments
while one-way ANOVA with Bonferroni’s post test was applied to in vitro experiments where applicable
Student’s T test was applied for comparisons when there were only two experimental groups to be analyzed
Tumour-cell invasion and migration: Diversity and escape mechanisms
The tumor microenvironment promotes cancer progression and cell migration
Cell matrix adhesions in cancer: The proteins that form the glue
Crystal structure of the extracellular segment of integrin alpha Vbeta3 in complex with an Arg-Gly-Asp ligand
The regulation of integrin function by divalent cations
The secreted factors responsible for pre-metastatic niche formation: Old sayings and new thoughts
The metastatic niche: Adapting the foreign soil
and intercellular interactions of exosomes and other extracellular vesicles
Membrane-derived microvesicles: Important and underappreciated mediators of cell-to-cell communication
The metastatic niche and stromal progression
Bone marrow cells in the ‘pre-metastatic niche’: Within bone and beyond
Melanoma exosomes educate bone marrow progenitor cells toward a pro-metastatic phenotype through MET
Molecular aspects of tumor cell migration and invasion
Syndecan and integrin interactomes: Large complexes in small spaces
Effect of sulfated glycosaminoglycans on tumor invasion and metastasis
Highly sulfated dermatan sulfates from Ascidians
Structure versus anticoagulant activity of these glycosaminoglycans
Heparin and heparan sulfate: Structure and function
The metallome of lung cancer and its potential use as biomarker
Molecular methods for assessment of non-covalent metallodrug-DNA interactions
Metal ions and the extracellular matrix in tumor migration
Manganese-induced integrin affinity maturation promotes recruitment of alpha V beta 3 integrin to focal adhesions in endothelial cells: Evidence for a role of phosphatidylinositol 3-kinase and Src
Manganese induces neurite outgrowth in PC12 cells via upregulation of alpha(v) integrins
copper and manganese enhanced keratinocyte migration through a functional modulation of keratinocyte integrins
Activation of ERK1 and ERK2 is required for manganese-induced neurite outgrowth in rat pheochromocytoma (PC12) cells
Manganese superoxide dismutase (SOD2/MnSOD)/catalase and SOD2/GPx1 ratios as biomarkers for tumor progression and metastasis in prostate
Manganese superoxide dismutase (Mn-SOD) correlates with prognosis of patients with oral squamous cell carcinoma
Differential effects of superoxide dismutase isoform expression on hydroperoxide-induced apoptosis in PC-12 cells
Manganese complex of ethylenediaminetetraacetic acid (EDTA)-benzothiazole aniline (BTA) conjugate as a potential liver-targeting MRI contrast agent
Facile deposition of manganese dioxide to albumin-bound paclitaxel nanoparticles for modulation of hypoxic tumor microenvironment to improve chemoradiation therapy
Manganese metabolism in rats: An improved methodology for assessing gut endogenous losses
Manganese neurotoxicity: Cellular effects and blood-brain barrier transport
Manganese promotes the aggregation and prion-like cell-to-cell exosomal transmission of α-synuclein
Tumour exosome integrins determine organotropic metastasis
Luminal iron levels govern intestinal tumorigenesis after Apc loss in vivo
Iron uptake via DMT1 integrates cell cycle with JAK-STAT3 signaling to promote colorectal tumorigenesis
Low DMT1 expression associates with increased oxidative phosphorylation and early recurrence in hepatocellular carcinoma
and ZnT10 in the regulation of systemic manganese homeostasis
Manganese transporter Slc30a10 controls physiological manganese excretion and toxicity
Mutations in SLC39A14 disrupt manganese homeostasis and cause childhood-onset parkinsonism–dystonia
Heparan sulfate proteoglycans may promote or inhibit cancer progression by interacting with integrins and affecting cell migration
Dually modified transmembrane proteoglycans in development and disease
The regulation of integrin function by Ca(2+)
Effect of manganese chloride and of cotreatment with cadmium chloride on the in vitro proliferative
motile and invasive behavior of MDA-MB231 breast cancer cells
λ-Carrageenan oligosaccharides of distinct anti-heparanase and anticoagulant activities inhibit MDA-MB-231 breast cancer cell migration
Structure and anticoagulant properties of sulfated glycosaminoglycans from primitive Chordates
Adipose mesenchymal cells-derived EVs alleviate DOCA-salt-induced hypertension by promoting cardio-renal protection
Trace elements during primordial plexiform network formation in human cerebral organoids
A simplified rapid method for the removal of iron and other cations from complex media
Fetal bovine serum impacts the observed N-glycosylation defects in TMEM165 KO HEK cells
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We would like to acknowledge Nathan Bessa and Bruno Pontes for aiding with cell migration time lapse videos; Felipe Souza for single-cell speed analyses; Felipe Teixeira and Wallace Abreu for aiding with animal procedures; Pedro Perdigão for collecting ascidians by freediving; Grasiella Ventura for confocal microscopy analyses; Rodrigo Madeiro for whole slice fluorescence imaging; and José Marcus Godoy and colleagues for ICP-OES analyses
This works was financially supported by CNPq
This research used resources of the Brazilian Synchrotron Light Laboratory (LNLS)
an open national facility operated by the Brazilian Centre for Research in Energy and Materials (CNPEM) for the Brazilian Ministry for Science
Funding was provided by Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (No
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (No
Conselho Nacional de Desenvolvimento Científico e Tecnológico (No
Ciência e Tecnologia do Rio de Janeiro and Fundação Ary Frauzino para Pesquisa e Controle do Câncer
These authors contributed equally: Mariana Paranhos Stelling
Mariana Alves Soares and Simone Coutinho Cardoso
Mariana Paranhos Stelling & Vitória Gonçalves de Freitas
Instituto de Bioquímica Médica Leopoldo de Meis
255 – Hospital Universitário Clementino Fraga Filho
Vitória Gonçalves de Freitas & Mauro Sérgio Gonçalves Pavão
Instituto de Ciências Biomédicas and Hospital Universitário Clementino Fraga Filho
Brazilian Synchrotron Light Laboratory (LNLS)
Brazilian Center for Research in Energy and Materials (CNPEM)
Laboratório de Bioquímica e Biologia Celular de Glicoconjugados
Hospital Universitário Clementino Fraga Filho
The authors declare no competing interests
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations
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the film never undersells the importance of brains being the most important sex organ
Which isn’t to say that it’s remotely straightforward
as a dying man is laid out like a display while a child plays with a toy fire truck
No sooner do you have your bearings than Rodrigues rewinds the clock back to the early aughts
flashing back to the moments when the dying man
His activism is established right off as being hopelessly intertwined with his maladroit sexuality; during a musical ode to the splendor of the pines
and their being “tumescent with sap,” Alfredo bashfully hides the erection he’s getting
He then attempts to transmute that fetish into action (in all senses of the word) by getting a job as a firefighter
in order to halt the spread of climate change-induced wildfires
the sexual heat of the firehouse is on full display from the moment Alfredo arrives to find crews performing field exercises
all under the watchful eye of the station’s salty fire chief
splendidly ripped from out of an alternate-universe John Waters film)
She sets up her new charge to train with Afonso (André Cabral)
and the sexual tension between the two—one a wispy descendent of white colonialists
the other a strapping Black member of the working class—is immediately apparent
which he co-wrote with João Rui Guerra da Mata and Paulo Lopes Graça
around the race and class differences represented by Alfredo and Afonso (there’s even a number set to the Portuguese song “Black on White”)
Rodrigues never drops the tone of frivolity
and despite the implicitly apocalyptic undertones of its century-hopping framing device
Will-o’-the-Wisp is Rodrigues’s Pierre et Gilles film: baroque
even the cocks being stroked are tres plastique
Rodrigues seems to be going for consistent
An early scene finds the station’s firemen quizzing Alfredo
on the various nude tableaux that they intend to reenact for the firehouse’s forthcoming erotic charity calendar
Alfredo is ultimately unable to identify the various
overtly sexualized parodies (such as Carvaggio’s Fireman’s Head and Francis Bacon’s Mr Fireman
only being familiar with the racist artifacts of colonial repute
Alfredo is laid out in front of José Conrado Roza’s Wedding Masquerade
which has been passed down in his family through generations
presumably since its 18th-century commissioning.)
Despite the philosophical implications of the sexy charade game
the meat of the scene is in the gentle-spirited naïveté exhibited by both Alfredo and the muscle-bound firefighters striking curious poses while wearing jockstraps
but in its final moments it still shares common bond with Rodrigues’s best work in that it never undersells the importance of brains being the most important sex organ
Eric Henderson is the web content manager for WCCO-TV
His writing has also appeared in City Pages
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Urban development in many cities around the world prioritizes making space for cars over pedestrians, cyclists or public transportation. In Brazil, this design led to an average of more than 30,000 annual road crash fatalities nationwide by the turn of the century
as well as high levels of congestion and pollution
At the heart of these changes is implementation of the “Complete Streets” concept
Many local governments aim to reduce traffic crashes only by changing drivers’ and passengers’ behaviors through things like seatbelt- and helmet-wearing campaigns
This approach puts the onus on individuals rather than the city to make streets safer
emphasizing the creation (or redesign) of streets that are safe
accessible and enjoyable for individuals of all ages and abilities
By providing infrastructure such as bike lanes
Complete Streets encourages active modes of transportation and reduces dependency on private vehicles
It’s also a good strategy for implementing traffic calming measures that reduce car speeds
Since Brazil passed its Federal Mobility Law in 2012
pedestrians and cyclists over cars and motorcycles
local governments are gradually shifting their policies and interventions toward this more equitable and efficient model
WRI Brasil worked with Brazil’s National Front of Mayors
Bloomberg Initiative for Global Road Safety and many other partners to support the implementation of 28 different Complete Street projects throughout the country in the last five years
While the goals of the projects vary — ranging from school zones to commercial streets to public transport hubs — each highlight how the Complete Streets approach can make public space more accessible
Here are three cities that illustrate these transformations:
João Alfredo Street wasn’t any different from other streets in the central area of Porto Alegre
the capital of Rio Grande do Sul in southern Brazil
The goal was to make the mixed-use street safer and more welcoming during the day for hundreds of school children
and at night for the many people who enjoyed going out to restaurants and nightclubs
The transformation was done in several stages
the city painted and installed curb extensions and roundabouts and existing ones were redesigned
The curb extensions shortened the distances for crossing the street
while roundabouts reduced speed in the intersections
Additional crossing lanes for pedestrians were also painted by the city and the posted speed limit was reduced from 40 kilometers per hour (25 miles per hour) to 30 kilometers (19 miles per hour)
an important change especially for improving the safety of children and the elderly
new street furniture was installed with vegetation
including litter bins and benches made by alumni from a social project in the neighborhood
The street was made safer by design
Spaces where people once passed by became places for socialization and rest for individuals and groups
Between 2016 and 2017, before the redesign, 60 crashes were reported on the street
After the new infrastructure was installed
the number of crashes dropped to 26 (-56%)
and the number of injured fell to seven (-61%)
Marquês do Paraná Avenue is one of the most important transport corridors in the city of Niterói
It’s also crucial for thousands of pedestrians and bicyclists who commute daily between residential neighborhoods and the city center
new development prioritized improving conditions for car traffic
resulting in less space for cyclists and pedestrians
There was also no dedicated infrastructure for public transport on most of Niterói’s streets
the city adopted a Complete Streets approach to transform a stretch of the avenue
shifting the priority to sustainable mobility
Thirty-five percent of the space once dedicated to cars is now dedicated to public transport
with improvements to sidewalks and bike lanes
The redesign also included a permanence space
This change represents a substantial gain in terms of environmental quality
creating a new comfortable public space in the neighborhood
which increased pavement permeability by 300%
and an underground reservoir with a capacity of capturing 60 cubic meters of rainwater help reduce flooding and improve safety
Delphino Cintra Street is an important access street to the city center of Campinas and was selected to be one of the flagships of the RevivaCidade program
an urban renewal program in the central area
Campinas is the third most populous city in the state of São Paulo
northwest of the city by the same name.
The area where Delphino Cintra Street is located has many hospitals and medical offices and had a significant number of crashes recorded in the area
the local government carried out a tactical transformation of the streets to reduce and organize traffic
and ensure the street was designed for permanence
the transformation generated new local dynamics
new benches and vegetation were implemented
The city collected data and found speeding was reduced by 38% for cars and 46% for motorcycles
Data also indicates that the new crosswalks have been well used
The percentage of pedestrians using the new crosswalks varied between 66% to almost 100%
which shows that these crossings were placed on the pedestrians’ desired lines. A survey by the city of Campinas revealed that 56.5% of the users approved of the new design
These results informed some design adjustments made during the second stage of implementation
new and more durable bollards and inclusion of a new safe area (a pedestrian refuge island
new crosswalks and accessible sidewalks were implemented)
survey results showed the approval rate reached 61%
Although Complete Streets often receives a lot of acceptance after implementation
that’s not always the case when new projects are announced
Common opponents include drivers who are used to having as much road space as possible
business owners fearful about the loss of parking spaces
and politicians and decision makers who are afraid of losing votes
Complete Streets projects tend to rely on budget and decisions from multiple city departments
This is challenging for the often-siloed operations of municipal departments
this provides an opportunity for a much-needed systemic shift in urban planning that promotes other important solutions
such as transport-oriented development and the adoption of nature-based solutions for climate adaptation
WRI Brasil’s work helping cities implement Complete Streets projects shows how these interventions are efficient and convincing tools for promoting cultural change towards healthier people-centered cities
It is still to be seen if Complete Streets and other sustainable urban development and mobility interventions will scale to more cities
But these good examples provide evidence for hope in Brazil and other countries seeking sustainable
equitable and people-centric urban mobility solutions
This article originally appeared on WRI’s Insights.
Bruno Batista is Active Mobility Analyst for WRI Brasil Ross Center for Sustainable Cities
Reynaldo Mello Neto is Senior Active Mobility Analyst for WRI Brasil Ross Center for Sustainable Cities
Fernando Correa is Communications Analyst for WRI Brasil
More cities are transforming their streets to increase space for walking and cycling
A “complete streets” intervention in Belo Horizonte
Photo by Rafael Tavares-Octopus Filmes/WRI Brasil
As the COVID-19 outbreak disrupts mobility worldwide, more and more cities are transforming their streets to increase space for walking and cycling and reduce car use during and after the pandemic
These changes are designed to help people get around while maintaining social distancing
but they can also help cities transition to a more resilient
For the concept of “complete streets,” the current moment may signal a tipping point
And for other potentially transformative urban solutions struggling to become mainstream
there is much to learn from this surge of cities adopting more expansive street redesigns
But not all street redesigns are successful over the long term. From our extensive experience working to test, pilot and implement complete streets interventions in more than 20 cities in Brazil
we reflect on lessons learned about how to create impactful and lasting change
These experiences can help cities looking to implement similar solutions in response to COVID-19
as well as other projects looking to transform cities at scale
Small-scale, quick and affordable changes in street design can generate a large impact. Such “tactical urbanism,” which can entail simply painting new pedestrian areas
installing low-cost street furniture or creating parklets out of parking spaces
can serve as a catalyst for broader change
Coupled with community engagement – especially with those who live
work or use the street with frequency – it allows people to experience the new design before permanent changes are implemented
learn about the benefits and very often build strong support for further changes
This strategy has proven effective for the implementation of complete streets projects across Brazil
Projects were executed faster because the changes were not necessarily permanent at the start and could be reversed
Data collected during pilot periods often showed tangible benefits
helping more pilot projects convert to permanent changes
Quick wins also encouraged city officials to try similar projects in other parts of the city
even increasing the scope of changes for a bigger impact
When executed in a way that’s responsive to community concerns and with a plan for the future – whether just a maintenance plan for a light intervention or more permanent infrastructure – tactical urbanism can be a strong ally of positive urban transformations by earning people’s trust
and keeping decision-makers and users alike motivated by seeing quick gains
Community engagement is key to the lasting success of tactical urbanism interventions like this low-speed zone project in Belo Horizonte
As cities face a growing list of challenges
it’s more important than ever that they share experiences and can understand what’s worked elsewhere
together with the National Front of Mayors
created a network of cities working to implement complete streets across the country
the initial number of cities working on complete streets projects in the country has already doubled from 10 in 2017 to 21 today
Such peer networks allow urban planners to exchange challenges and lessons learned
helping each other to overcome local problems and deliver better projects
they end up evolving projects faster by pushing each other and acting a bit like a team focused on a shared vision of improving streets for residents
The success of coalitions very much relies on two aspects
a good governance structure that allows for a smooth relationship among participant cities and the organization that coordinates them
creating an easy-to-access platform for sharing experiences like a WhatsApp group
and hosting in-person meetings once or twice a year for deeper connections help people feel connected and motivated
Building trust is essential to allow a seamless flow of activities by different actors and achieving tangible outcomes
it’s important to keep the network engaged
like developing pilot projects or presenting good practices in a webinar
Communicating achievements to the public also helps reward good actors and create positive feedback loops
Creating a safer intersection for pedestrians on busy João Alfredo Street in Porto Alegre
A common frustration among city officials is when good projects are shelved for years because there is reluctance to challenge the status quo or a new government enters office and existing projects are paused in favor of different political priorities
Tactical urbanism and city networks have both helped short-circuit this dynamic in Brazil by lowering the bar for starting a project and expanding the framing for change beyond the agenda of one mayor or another
And the changes are being enacted not only to improve the use of public space but explicitly because of the potential of walking and cycling to contribute to a more sustainable and livable city too – in short
Designing safe intersections that incorporate the new road dynamics and connecting existing pedestrian and cycling lanes to any new infrastructure are also key elements to ensure changes connect to the broader urban mobility network
These details may take more time to get right
but they help ensure the success and sustainability of a project
The João Alfredo Street intervention in Porto Alegre included painted sidewalk extensions and bollards to improve safety for cyclists too
But it’s those cities that adapt fastest and are able to sustain transformative change that will benefit most from these changes
Paula Manoela dos Santos is the Active Mobility Manager at WRI Brasil Ross Center for Sustainable Cities
Francisco Minella Pasqual is an Urban Mobility Assistant at WRI Brasil Ross Center for Sustainable Cities
Fernando Corrêa is a Communications Analyst for WRI Brasil.
The 7th edition of the Eddie Bravo Invitational will take part on July 16, 2016 (Saturday). EBI 7 will be crowning the promotion’s featherweight (145lbs / 65kg) division champion, a title currently held by Eddie Cummings.
Although the open weight tournament (EBI 6) included big names of jiu jitsu’s international circuit, this featherweight event will have the popular tournament return to its origins in a recipe that rose the attention of the sport’s fans in previous showings, a mix of veteran grapplers, fairly unknown talent and rising stars of the submission only movement.
Find out more about each EBI title contender below.
NFW that BTG is going to be competing at 145. Has to be a typo.
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Study reconstructs the role of the abolitionist movement as a social force that led to the freeing of slaves
Public Domain Image Open-air mass in celebration of abolition and illustration depicting an abolitionist, two slaves, and ParliamentPublic Domain Image
Public Domain Image Abolitionist confederation in 1888, with José do Patrocínio (standing, first on left) and André Rebouças (seated, first on left)Public Domain Image
Public Domain Image Parliament during voting of the Golden Law in 1888…Public Domain Image
Public Domain Image …and the crowd outside: the text of the law was cut to the minimum necessaryPublic Domain Image
Judicial activism The strategy spawned a nationwide campaign
which was successful mainly in Ceará and Amazonas
provinces that had relatively few slaves and counted on abolitionist governors
the movement resulted in the abolition of slavery within province borders in 1884
and the territory became a destination for runaway slaves and freedmen from all over the country
Another strategy that drew its inspiration from abroad was that of Luiz Gama
who looked for legal loopholes and petitioned the court to grant slaves their freedom
“Gama was part of a faction of abolitionism that defended judicial activism
who believed reform should come through parliament,” says Fonseca
Alonso argues that “they didn’t strictly disagree
each relying on a different style of activism.”
The freeing of the slaves in Ceará ushered in the “vote” phase
When Sousa Dantas was appointed to head the imperial government in 1884
abolitionists helped draft the government’s program and launched 51 candidates in support of it
“less at the polls than in the counting,” according to Alonso
Cotegipe’s pro-slavery government took over
with the police force and plainclothes militias openly and fiercely repressing abolitionist activities
“It was at this point that the process of civil disobedience burgeoned,” the researcher says
José do Patrocínio declared that “true abolitionists are prepared to die.” In the opinion of the historian Carlos Castilho
professor at Vanderbilt University in the United States
this attests to the valuable role that social movements played in this process
“The struggles for political and civic participation have their own histories
and historiography needs to rethink them,” says Castilho
Thanks largely to abolitionism as a social movement
abolitionism enjoyed the tacit support of the urban population
which remained silent about runaway slaves,” says Alonso
“Slavery was eaten away at from all sides.” Yet the process ended in a stalemate
but the abolitionists were unable to implement their program to extend rights to freedmen
The cabinet of João Alfredo Correa de Oliveira – prime minister to Emperor Pedro II – triumphed in its effort to make the Golden Law a mere two-paragraph declaration that did not compensate slave owners for their losses but also did not guarantee former slaves a dignified life
University of São Paulo/Brazilian Center for Analysis and Planning); Investment R$ 116,566.11
votos e balas – O movimento abolicionista brasileiro (1868-88) (Flowers
and bullets: the Brazilian abolitionist movement [1868-1888])
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which taxes online sports operators between 8% and 16% of turnover
and casino operators between 15% and 30% of GGR
has proved controversial ever since its inception in 2015
“EGBA urges the authorities to apply equal taxes across all online gambling products – and based on gross gaming revenue.”
“A sensible taxation level will lead to better priced betting odds
and pull into the regulated market more of the 75%t of Portuguese players who are now playing on websites not regulated in Portugal.”
The recommendation comes after ongoing calls from online firms to change the tax rate
which has driven international operators out of the market
with a recent report by the Universidade NOVA de Lisboa revealing that visits to unregulated sites increased by ten percent during 2018
The Portuguese government formed a multi-ministry committee to discuss changes to the tax scheme on 28 January
however the inclusion of state-owned lottery monopoly Santa Casa in proceedings led some commentators to question its efficacy
“They are not very interested in having online gambling and betting with a tax regime that invites more players and more operators,” observed gaming lawyer Joao Alfredo Afonso at the time
“It will be directly competing with their land-based monopoly.”
In prolonging an exclusionary tax programme
the Portuguese government is only succeeding in driving players toward sites it claims it is protecting against
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